I'm a new 2018 VW Alltrack owner, only 1000Km on the car and less than a month old. I began having issues only a few days into owning the car with electrical problems, began to see warning lights with airbag, front assist, park assist, ESC, etc. The problems would only crop up after it rained or during a rainfall. After a couple trips to the dealership the service department started tracing some wiring and found them to be all wet with water coming down the frame.
After they took it all apart it was determined the panoramic sunroof was leaking due to a problem with a gap between the frame and the roof (I imagine the same scenario described in another post with a bad weld). They are now in the process of replacing the sunroof, headliner, wiring and ABS module. I don't have a lot of detail on this as I am new to VW and still trying to figure out how water got down the front side to even cause damage to all the wiring. Only thought I have is a park reversed into my driveway it's got quite the grade to it so in rain shower/storm the water would flow to the front not the rear for me (only a guess). I didn't see any water damage to the headliner but the service manager indicated that it was damp and I would have eventually seen it had it not come in with the electrical problems first. My dealership indicated that had never seen this before so I am hoping the 2 are related and fixed up as this is a brand new car, they are probably looking at 3 weeks worth of repairs to get this resolved.
So it looks like this is still an issue in the 2018 models, I saw it stated earlier that this would hopefully be resolved on the '18 model year but that looks like a hard no on this.
This will probably be my first and last VW, seems ridiculous to have this type of an issue on a car, I will say so far the dealership and service department have been good but time will tell.